1. [MAXIMUM GRIP STRENGTH]Strengthen your arms and wrists for deep workouts in the gym; train your muscles for better grip strength or re-educate your upper limbs after injuries - the new ALL-METAL Grip Strengthener from Powerball gives you everything you need, all in one powerful and compact product.^ 2. [FOR ALL LEVELS]With several resistance levels available, there's a metal grip Powerball that's suitable for all strength and fitness levels.^ 3. [TREAT & PREVENT INJURIES]These metal strengtheners are highly effective for both rehabilitation and muscle building. Start with a low resistance Gripper and move up the levels as you get stronger and heal. It is the ideal product to prevent (musculoskeletal disorders caused by repetitive movements) such as carpal tunnel syndrome, tendonitis, etc.^ 4. [EASY TO USE] Squeeze the bars for a few seconds at a time or release and squeeze for concentric and eccentric strengthening - you control the intensity of your workout; just squeeze with your fingers for an immediate effect.^ 5. [PROFESSIONAL QUALITY] Stainless steel springs and aluminum handles with diamond engravings for better grip. In addition, each one comes with a comprehensive training guide to help you maximize your strength training and rehabilitation results.^